The Granary increases the Food production of a city, speeding up the city's growth, especially if it has one of the above-mentioned resources nearby. It's useful when you want to create a large city, fast. Also, it's incredibly useful in cities with access to little or no fertile land.

A granary is a building constructed to store grain for human or herd animal consumption (or both). The earliest granaries yet discovered were found in a pre-pottery Neolithic settlement in the Jordan Valley of the Middle East, and date back to approximately 9500 BC. These first granaries measured about 10-foot by 10-foot square. They featured raised floors which allowed air to circulate more freely and provided some protection for the grain from mice and other menaces.